Metal cutting - oxyfuel cutting, plasma cutting, machining, grinding, and other preparatory work.
Post Reply
Spartan
  • Posts:
  • Joined:
    Fri Mar 06, 2020 8:59 pm

Welp, had at least 2 hours invested into machining this ~4" bearing hub. Went to do the final parting and the tool snagged and ripped the part right out of the chuck. Broke the tool, and ruined the part in the process.

Lessons learned:

- Make sure the compound angle is actually zeroed (it was on about 1 degree). Oooops.
- Hold more of the part in the chuck when parting. I only had about 5/8" to hold onto with the way I had the setup...certainly not ideal for parting, and I should have considered that.
- I was rushing to get it done. Don't rush.

Expensive mistakes for both me and the customer.
IMG_2213.jpg
IMG_2213.jpg (77.78 KiB) Viewed 1567 times
IMG_2214.jpg
IMG_2214.jpg (29.55 KiB) Viewed 1567 times
IMG_2215.jpg
IMG_2215.jpg (29.84 KiB) Viewed 1567 times
IMG_2216.jpg
IMG_2216.jpg (34.77 KiB) Viewed 1567 times
User avatar
  • Posts:
  • Joined:
    Wed Dec 20, 2017 8:37 pm
  • Location:
    Clovis CA

Good news
At least it was not brass.

Dave
Spartan wrote:Welp, had at least 2 hours invested into machining this ~4" bearing hub. Went to do the final parting and the tool snagged and ripped the part right out of the chuck. Broke the tool, and ruined the part in the process.

Lessons learned:

- Make sure the compound angle is actually zeroed (it was on about 1 degree). Oooops.
- Hold more of the part in the chuck when parting. I only had about 5/8" to hold onto with the way I had the setup...certainly not ideal for parting, and I should have considered that.
- I was rushing to get it done. Don't rush.

Expensive mistakes for both me and the customer.
IMG_2213.jpg
IMG_2214.jpg
IMG_2215.jpg
IMG_2216.jpg
DavidR8
  • Posts:
  • Joined:
    Fri Apr 17, 2020 12:50 am
  • Location:
    Vancouver, Canada

Ugh. Been there. Feel your annoyance!


Sent from my iPhone using Tapatalk
David
Millermatic 130
Primeweld 225
noddybrian
  • Posts:
  • Joined:
    Thu Jan 24, 2013 12:13 pm

I hate it when that happens - one word of advice - stop parting off with the tool facing up - if you only part off with the tool facing down this almost never happens - I used to have similar disasters & an apprehension over parting - then I made a taller tool post to allow upside down mounting but this meant having to stop & reverse every time which on repetitive stuff gets old so now I've made a rear post - problem solved - I also like the mist coolant rather than flood as it really gets in deep grooves & blasts the chip clear.
BillE.Dee
  • Posts:
  • Joined:
    Mon Nov 27, 2017 8:53 pm
  • Location:
    Pennsylvania (Northeast corner)

OUCH !! Sorry to read about that, Spartan. A few years ago a friend of mine was working with molybdenum bars. He wasn't watching "everywhere", bumped one of the bars, "it" rolled off the table, bounced on the floor and made many more bars. LOTS of multi syllable words, huge delay and expense.
Again, sorry, but nobody got hurt.
Post Reply